The high road and the low road: trafficking choices in plants

Polar transport of the signaling molecule auxin is critical for plant development and depends on both the polar distribution of auxin efflux carriers, which pump auxin out of the cell and the alignment of these polarized cells. Two papers in this issue of Cell (Michniewicz et al., 2007; Jaillais et al., 2007) address how polar transport of these carriers occurs and describe the endosomal pathways involved.     

Introduction to placebo effects in medicine: mechanisms and clinical implications

The field of placebo research has made considerable progress in the last years and it has become a major focus of interest. We know now that the placebo effect is a real neurobiological phenomenon and that the brain's 'inner pharmacy' is a critical determinant for the occurrence of psychobiological and behavioural changes relevant to healing processes and well-being. However, harnessing the advantages of placebo effects in healthcare is still a challenge. The first part of the theme issue summarizes and discusses the various kinds of placebo mechanisms across medical fields, thereby not only focusing on two main explanatory models-expectation and conditioning theory-but also taking into account empathy and social learning, emotion and motivation, spirituality and the healing ritual. The second part of the issue focuses on questions related to transferring knowledge from placebo research into clinical practice and discusses implications for the design and interpretation of clinical trials, for the therapeutic settings in daily patient care, and for future translational placebo research.     

Changes in clinical profile, treatment, and mortality in patients hospitalised for acute myocardial infarction between 1985 and 2008

Objectives

To quantify the impact of the implementation of treatment modalities into clinical practice since 1985, on outcome of patients with ST-segment elevation myocardial infarction (STEMI) or non-ST-segment elevation myocardial infarction (NSTEMI).

Methods

All consecutive patients admitted for STEMI or NSTEMI at the Thoraxcenter between 1985 and 2008 were included. Baseline characteristics, pharmacological and invasive treatment modalities, and survival status were collected. The study population was categorised in three groups of patients: those hospitalised between 1985–1990, 1990–2000, and 2000–2008.

Results

We identified 14,434 patients hospitalised for myocardial infarction (MI). Both STEMI and NSTEMI patients were increasingly treated with the current guideline based therapy. In STEMI, at 30 days following admission, cumulative mortality rate decreased from 17% in 1985–1990 to 13% in 1990–2000, and to 6% in 2000–2008. Adjusted 30-day and three-year mortality in the last period was 80% and 68% lower than in 1985, respectively. In NSTEMI, at 30 days following admission, cumulative mortality rate decreased from 6% in 1985–1990 to 4% in 1990–2000, and to 2% in 2000–2008. Adjusted 30-day and three-year mortality in the last period was 78% and 49% lower than in 1985, respectively. For patients admitted between 2000 and 2008, 3 year survival of STEMI and NSTEMI patients was 87% and 88%, respectively.

Conclusions

Our results indicate substantial improvements in acute- and long-term survival in patients hospitalised for MI, related to improved acute- as well as long-term treatment. Early medical evaluation in suspected MI and intensive early hospital treatment both remain warranted in the future.     

ROCR: visualizing classifier performance in R

SUMMARY: ROCR is a package for evaluating and visualizing the performance of scoring classifiers in the statistical language R. It features over 25 performance measures that can be freely combined to create two-dimensional performance curves. Standard methods for investigating trade-offs between specific performance measures are available within a uniform framework, including receiver operating characteristic (ROC) graphs, precision/recall plots, lift charts and cost curves. ROCR integrates tightly with R's powerful graphics capabilities, thus allowing for highly adjustable plots. Being equipped with only three commands and reasonable default values for optional parameters, ROCR combines flexibility with ease of usage. AVAILABILITY: http://rocr.bioinf.mpi-sb.mpg.de. ROCR can be used under the terms of the GNU General Public License. Running within R, it is platform-independent. CONTACT: tobias.sing@mpi-sb.mpg.de.     

In vitro measurement of cell death with the annexin A5 affinity assay

One of the hallmarks of cell death is the cell surface-expression of phosphatidylserine. Expression of phosphatidylserine at the cell surface can be measured in vitro with the phosphatidylserine-binding protein annexin A5 conjugated to fluorochromes. This measurement can be made by flow cytometry or by confocal scanning-laser microscopy. The annexin A5 affinity assay comprises the incubation of cells stimulated to execute cell death with fluorescence-labeled annexin A5 and propidium iodide. Living cells are annexin A5-negative and propidium iodide negative, cells in the early phases of cell death are annexin A5 positive-and propidium iodide-negative, and secondary necrotic cells are annexin A5-positive and propidium iodide-positive. The entire procedure takes about 30 minutes for flow cytometry and 45 minutes for confocal scanning-laser microscopy. Various precautions and considerations are discussed further in the protocol described here.     

Site-specific labeling of ‘second generation’ annexin V with 99mTc(CO)3 for improved imaging of apoptosis in vivo

In this study ‘second generation’ AnxV was specifically labeled with ^99mTc in three different ways outside the binding region of the protein to obtain an improved target-to-background activity ratio. The compounds were tested in vitro and in vivo in normal mice and in a model of hepatic apoptosis (anti-Fas mAb). The apoptosis binding was most prominent for the HIS-tagged ‘second generation’ AnxV labeled with ^99mTc(CO)₃ in comparison to ^99mTc-HYNIC-cys-AnxV and ^99mTc(CO)₃-DTPA-cys-AnxV.     

Weighing risk factors associated with bee colony collapse disorder by classification and regression tree analysis

Colony collapse disorder (CCD), a syndrome whose defining trait is the rapid loss of adult worker honey bees, Apis mellifera L., is thought to be responsible for a minority of the large overwintering losses experienced by U.S. beekeepers since the winter 2006-2007. Using the same data set developed to perform a monofactorial analysis (PloS ONE 4: e6481, 2009), we conducted a classification and regression tree (CART) analysis in an attempt to better understand the relative importance and interrelations among different risk variables in explaining CCD. Fifty-five exploratory variables were used to construct two CART models: one model with and one model without a cost of misclassifying a CCD-diagnosed colony as a non-CCD colony. The resulting model tree that permitted for misclassification had a sensitivity and specificity of 85 and 74%, respectively. Although factors measuring colony stress (e.g., adult bee physiological measures, such as fluctuating asymmetry or mass of head) were important discriminating values, six of the 19 variables having the greatest discriminatory value were pesticide levels in different hive matrices. Notably, coumaphos levels in brood (a miticide commonly used by beekeepers) had the highest discriminatory value and were highest in control (healthy) colonies. Our CART analysis provides evidence that CCD is probably the result of several factors acting in concert, making afflicted colonies more susceptible to disease. This analysis highlights several areas that warrant further attention, including the effect of sublethal pesticide exposure on pathogen prevalence and the role of variability in bee tolerance to pesticides on colony survivorship.     

Selected markers of endothelial dysfunction in patients with subclinical and overt hyperthyroidism

INTRODUCTION: There are many factors causing endothelial dysfunction. The aim was to observe chosen markers of endothelial function in patients with subclinical and overt hyperthyroidism. MATERIAL AND METHODS: We studied 97 patients with hyperthyroidism: 51 with subclinical (44 F/7 M; mean age 49.3 +/- 15.9 y) and 46 patients with overt (39 F/7 M, mean age 50.4 +/- 13.2 y). The control comprised of 39 healthy volunteers (26 F/13 M, mean age 47.5 +/- 11.8 y). Concentration of TSH, FT3, FT4 were measured by MEIA, TPO Ab, TG Ab, E-selectin, interleukin 6, VCAM-1, ICAM-1 by ELISA. RESULTS: The goiter was found in 71 persons 63F/8M, mean age 49.9 +/- 15.3 y, (42-subclinical, 29-overt). Morbus Graves-Basedow was diagnosed in 26 persons, 20 F/6 M, mean age 49.5 +/- 12.8 y (9-subclinical, 17-overt). There were no significant differences serum concentration of E-selectin, IL-6, ICAM-1 in patients with subclinical and overt hyperthyroidism compared to the control. Statistically significant differences were shown between concentration of IL-6 in patients with Graves-Basedow compared with the control (p < 0.05). Significance of VCAM-1 values were found in the patients with subclinical and overt hyperthyroidism compared to the control (p < 0.001; p < 0.001, respectively). CONCLUSIONS: Among persons with overt and subclinical hyperthyroidism occurs endothelial dysfunction which doesn't depends on exciting cause of thyrotoxicosis but on degree of hyperthyroidism. Elevated concentrations of endothelial markers may confirm that persons with thyroid disorders are extremely exposed to the occurrence of the cardiovascular diseases.     

A hormone and proteome approach to picturing the initial metabolic events during Plasmodiophora brassicae infection on Arabidopsis

We report on the early response of Arabidopsis thaliana to the obligate biotrophic pathogen Plasmodiophora brassicae at the hormone and proteome level. Using a CYCB1;1::GUS construct, the re-initiation of infection-related cell division is shown from 4 days after inoculation on. Sensitivity to cytokinins and auxins as well as the endogenous hormone levels are evaluated. Both an enhanced cytokinin gene response and an accumulation of isopentenyl adenine and adenosine precede this re-initiation of cell division, whereas an enhanced auxin gene response is observed from 6 days after inoculation on. The alhl mutant, impaired in the cross talk between ethylene and auxins, is resistant to P. brassicae. A differential protein analysis of infected versus noninfected roots and hypocotyls was performed using two-dimensional gel electrophoresis and quantitative image analysis, coupled to matrix-assisted laser desorption ionization time of flight-time of flight mass spectrometry-based protein identification. Of the visualized proteins, 12% show altered abundance compared with the noninfected plants, including proteins involved in metabolism, cell defense, cell differentiation, and detoxification. Combining the hormone and proteome data, we postulate that, at the very first stages of Plasmodiophora infection, plasmodial-produced cytokinins trigger a local re-initiation of cell division in the root cortex. Consequently, a de novo meristematic area is established that acts as a sink for host-derived indole-3-acetic acid, carbohydrates, nitrogen, and energy to maintain the pathogen and to trigger gall development.